Guys,
Tennadyne has a web site http://www.tennadyne.com
They have some good reading from the manufacturer
explaining how gain is indeed sacrificed for
bandwidth. Unfortunately they ruin the discussion
with a testimonial which puts one of antennas 5 to
10 db above a popular tribander. (Implying thier
gain approaches 15db!)
They list specs for their various antennas--
including db gain over a dipole (no frequency
given).
For example the T6 is 6 elements on a 12 foot boom
and a T10 is 10 elements on a 24 foot boom.
I can't possibly see how a T6 "kicks butt" as one
testimonial here put it.
It is interesting to note that the claimed gain
figures show 5.1 dbd for the 12 ft boom case (no
frequency stated) and 6.5 dbd for the T12 30'
case. I compared this to W2PV's gain vs boom
length correlation (yagi's) for the case of 20M.
For these relatively short booms Lawson's
correlation shows an increase of more than double
this 1.4db going from a 12' to a 30' boom. It
seems that the LPDA has very little gain
improvement for going from 12 to 30'. I wonder
just what one does get for the extra 6 elements,
18 foot of boom and $500?
Brian/K3KO
73
de Brian/K3KO
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